What causes radio no power in the 2004 chevy silverado?

First, let's be clear, are You getting no power at all to the radio, or does the radio turn on, but give You now sound The 2004Chevrolet Silverado has the same electrical settings as previous models, so if You've played with the radio wires before, You should feel comfortable with it here. If the issue is no sound, then You're looking at the speakers having been blown, or wiring issue, and potentially a fuse. If there's no power at all (and I'm assuming this isn't a situation where Your car isn't starting either, because, come on, it's Your battery! ) to the unit, the most likely cause is going to be a blown fuse. You can usually replace it for under ten dollars, and the fuse box for the car stereo is on Your driver's side, in that panel. If it isn't the fuse, You most likely have a disconnected or otherwise compromised wire, which You're going to have to trace from the back of the unit through the engine.